Specman e 列出约束参考

Question

我正在尝试执行以下操作：

unit parent {
              sons: list of sons is instance;
              grands: list of grands is instance;

              keep sons.size() == 4;
              keep grands.size() == 4;
};

unit sons {
            grands:list of grands is instance;
            keep grands == get_enclosing_unit(parent).grands.all( .id > 3 );

           //this is not working
           keep for each in grands {
              it.parent_age == 70;
           };
};

unit grands {
           id: uint;
           parent_age:uint;
};

extend sys {
   p : parent is instance;
   run() is also {
      print p;
      for each (s) in p.sons {
         print s;
      };
      for each (g) in p.grands {
         print g;
      };

   };
};

换句话说，我希望儿子列表指向父母列表的一部分，但仍然能够约束（不工作的部分）来自儿子单元/结构的孙子列表。

使用 9.20 上的 PGen 约束引擎，以上代码会生成：

Starting the test ...
Running the test ...
  p = parent-@0: parent   e_path: sys.p
  hdl_path:
        ----------------------------------------------  @tmp
0       sons:                           (4 items)
1       grands:                         (4 items)
  s = sons-@1: sons   e_path: sys.p.sons[0]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (empty)
  s = sons-@2: sons   e_path: sys.p.sons[1]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (empty)
  s = sons-@3: sons   e_path: sys.p.sons[2]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (empty)
  s = sons-@4: sons   e_path: sys.p.sons[3]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (empty)
  g = grands-@5: grands   e_path: sys.p.grands[0]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             4107502109
1       parent_age:                     3829340118
  g = grands-@6: grands   e_path: sys.p.grands[1]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             3657005019
1       parent_age:                     2354335776
  g = grands-@7: grands   e_path: sys.p.grands[2]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             3238917208
1       parent_age:                     336300761
  g = grands-@8: grands   e_path: sys.p.grands[3]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             1416976666
1       parent_age:                     2212224392

使用 Specman 9.20 上的 IntelliGen 约束引擎，以上代码会生成：

Starting the test ...
Running the test ...
  p = parent-@0: parent   e_path: sys.p
  hdl_path:
        ----------------------------------------------  @tmp
0       sons:                           (4 items)
1       grands:                         (4 items)
  s = sons-@1: sons   e_path: sys.p.sons[0]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (4 items)
  s = sons-@2: sons   e_path: sys.p.sons[1]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (4 items)
  s = sons-@3: sons   e_path: sys.p.sons[2]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (4 items)
  s = sons-@4: sons   e_path: sys.p.sons[3]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (4 items)
  g = grands-@5: grands   e_path: sys.p.grands[0]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             619055518
1       parent_age:                     4122406610
  g = grands-@6: grands   e_path: sys.p.grands[1]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             2908565159
1       parent_age:                     1741309063
  g = grands-@7: grands   e_path: sys.p.grands[2]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             3091108084
1       parent_age:                     1231835435
  g = grands-@8: grands   e_path: sys.p.grands[3]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             1717477430
1       parent_age:                     937745175
No actual running requested.
Checking the test ...
Checking is complete - 0 DUT errors, 0 DUT warnings.

Answer 1

我认为您存在生成顺序冲突：

• 根据 grands.id 字段填充 sons.grands 列表，这意味着您必须生成 grands< /code> 首先列出。
• grands.parent_age 取决于 sons parent_age == 70 约束，这意味着您必须生成 sons先列出来。

解决这个代码问题的最简单、最直接的方法（我知道你给出了一个简单的例子）是：

extend parent {
   keep for each (g) in grands {
      ( g.id > 3 ) => g.parent_age == 70;
   };
};

经过更多测试，我很确定它是一个组合约束排序问题与方法调用。 Specman 生成器不会遵循 sons' grand 列表约束上的约束，除非您在不执行方法调用的情况下设置这些指针。

<'
unit parent {
   sons: list of sons is instance;     // <-- swapped these two lines
   grands: list of grands is instance; // <-- to do constraint ordering in IntelliGen
                                       //     even though Cadence says you don't need
                                       //     to
   keep for each (s) in sons {
      s.grands == grands; -- .all( .id > 3 ); -- removed the 'all' and 'get_enclosing_unit' invocation
   };

   keep sons.size() == 4;
   keep grands.size() == 4;
};

unit sons {
   grands:list of grands is instance;
   --keep grands == get_enclosing_unit(parent).grands.all( .id > 3 );

   //this is not working
   keep for each in grands {
      it.parent_age == 70;
   };
};       

unit grands {
   id: uint;
   parent_age:uint;
};

extend sys {
   p : parent is instance;
   run() is also {
      print p;
      for each (s) in p.sons {
         print s;
      };
      for each (g) in p.grands {
         print g;
      };
   };
};   
'>

使用IntelliGen（不适用于 PGen ）：

Starting the test ...
Running the test ...
  p = parent-@0: parent   e_path: sys.p
  hdl_path:
        ----------------------------------------------  @tmp
0       sons:                           (4 items)
1       grands:                         (26 items)
  s = sons-@1: sons   e_path: sys.p.sons[0]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (26 items)
  s = sons-@2: sons   e_path: sys.p.sons[1]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (26 items)
  s = sons-@3: sons   e_path: sys.p.sons[2]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (26 items)
  s = sons-@4: sons   e_path: sys.p.sons[3]
  hdl_path:
        ----------------------------------------------  @tmp
0       grands:                         (26 items)
  g = grands-@5: grands   e_path: sys.p.sons[3].grands[0]
  hdl_path:
        ----------------------------------------------  @tmp
0       id:                             4093923439
1       parent_age:                     70 
[snip]

您可能需要考虑直接使用pre_generate()/post_generate()。您还可以查看 Cisco 开源的 csco_config 软件包 （此处）。我们使用该包在我们的环境中进行奇怪的约束和约束传播。但是，大多数约束都是自上而下的，而您的示例似乎是关于同行互相修改的。

另一份设计说明。 5 级列表相互约束是一个维护问题。理想情况下，每个级别最多只应了解其子列表和父列表。提供一个字段，然后将该字段向下传递到较低的级别，将使每个级别不必了解所有其他级别。然而，我知道违反设计准则是有原因的:-)